SOLUTION: XYZ Corporation gives each of its employees an aptitude test. The scores on the test are normally distributed with a mean of 77 and a standard deviation of 12. A simple random samp
Algebra ->
Probability-and-statistics
-> SOLUTION: XYZ Corporation gives each of its employees an aptitude test. The scores on the test are normally distributed with a mean of 77 and a standard deviation of 12. A simple random samp
Log On
Question 1072249: XYZ Corporation gives each of its employees an aptitude test. The scores on the test are normally distributed with a mean of 77 and a standard deviation of 12. A simple random sample of 26 is taken from a population of 500. What is the probability that the average aptitude test in the sample will be greater than 81.68 (to 4 decimals)? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! mean 77, sd 12
z=(x-mean)/s/sqrt(n)
>=4.68/(12/sqrt(26)=4.68*sqrt (26)/12=1.989
The probability z>1.989 is 0.0234; note, if you use 1.99, you get 0.0233
